Research And Design On Vehicle Data Acquisition System Of Electrical Vehicle

Design and implement of VDAS(Vehicle Data Acquisition System) of FCEV(Fuel Cell Electric Vehicle), is described in detail in this paper. The aim of the system design is to synchronously capture and memory many parameters values of FCEV in order to supply abundance data for optimizing and establishing the vehicle control system strategy of FCEV.At first, the structure of distributing fiber CAN bus net, which is data source of VDAS, is introduced in this paper. By compared with several VDAS blue prints, the VDAS design based on USB host is put forward. And some protocol contents are introduced.Then, hardware design and bottom driver software design are described in detail. Hardware design of the data acquisition is about the chip selecting, data acquisition circuit design and EMC design. Bottom driver controls the data acquisition, data transmission and data storage. It cites many protocols such as USB, Mass Storage, CAN, FAT16, so it is the most complex part in the whole system design. Program language C is used for microcontroller firmware design, which includes data received and sent on CAN bus net, USB host software system aiming at USB Mass Storage device and data storage.Finally, off-line analyse of acquired data, based on Borland C++ Build, is introduced.There are some advantages compared with existing vehicle data acquisition system:1. USB host is used for data transmission and storage. That can directly store acquired data in USB Mass Storage device without PC.2. Data storage carrier is USB Mass Storage device, which is cheap, and having a small size and low power. That reduces the cost and size of hardware design and the power of the data acquisition system, while increases the reliability, convenience and versatility of the system.3. Modular programming design of USB host software reduces the degree of difficulty of the software design, and conveniences user software upgrade and maintenance.During vehicle running, the system runs stabilization and acquires data fully and accurately. During analyzing off-line data, the data curve can show vehicle running status actually.